Many surgical procedures require positioning a patient on a surgical and/or procedure table in a certain way. The positioning may facilitate surgical and/or procedure access, shift a patient's organs in a certain direction, or increase or decrease blood flow to certain organs. Such positioning may include the left or right lateral tilting of the patient; the independent raising or lowering of the torso, seat, head and extremities of the patient; adjustment into the Trendelenburg position (head down, legs elevated) and reverse Trendelenburg position (head elevated, legs down); and adjustment into the flex position (head down, midsection up, feet down) and reflex position (head up, midsection down, feet up).
For example, the Trendelenburg position may be used to treat various conditions by increasing venous return and blood flow to a patient's heart to minimize the risk of shock. During subclavian or internal jugular access procedures involving cannulation, it is often necessary to increase venous return for vasodilitation (i.e., increasing the caliber of blood vessels) to facilitate the cannulation process. Additionally, during acute vagal responses, transient vascular and neurogenic reactions marked by a sudden decrease in heart rate and rapid fall in arterial blood pressure, prompt action is required. Further, acute hypotensive patients may benefit tremendously by increasing their cardiac output.
Reverse Trendelenburg positioning, which involves elevating the head, has been found useful to facilitate access to difficult to reach areas of the body. For example, such a position may use gravity to shift organs to a desired position.
Raising a patient's midsection has been found desirable during pericardiocentesis procedures, which entail inserting a pericardiocentesis needle just below the sternum (xyphoid process) to evaluate the cause of a chronic or recurrent pericardial effusion or to relieve cardiac tamponade. Such a position has also been found useful during acute pulmonary edema.
While various surgical and/or procedure tables having articulated tabletops may accomplish a desired range of motions, they have several drawbacks. First, many such tables are complex and not easily manipulated to desired positions. Additionally, because they are costly, such tables are often unavailable.
Another problem with conventional surgical tables (including those with articulated tabletops) is that patients often find the mattresses extremely uncomfortable. These mattresses tend to be thin, offering little or no support for certain areas of the body (e.g., the lumbar region).
Furthermore, conventional inflatable mattresses do not provide the range of elevations required to achieve the desired range of positions. Elevations of portions of a mattress of 18 inches or more may be required to achieve desired positioning of a patient during surgery and/or other procedures. While inflatable mattresses generally provide adjustable support and firmness characteristics, they typically accommodate a relatively limited range of positions.
Conventional surgical tables and mattresses do not address the thermal comfort and stability of the patient, which may require heating or cooling. During some procedures, such as open heart surgery and hyperthermia treatment, cooling may be desired. The benefits of maintaining normothermia are well known. Peri-operative hypothermia can have serious side effects for any patient, including a decrease in cardiovascular stability, an increase in oxygen consumption, and a decrease in resistance to infection.
Yet another disadvantage of conventional surgical tables and mattresses is that they do not provide means for reducing the risk of bed sores. Patients, particularly elderly and bedridden patients, may develop bed sores (i.e., decubitis or pressure ulcers) after a relatively short period of time due to the reduction of blood flow and therefor oxygen to soft tissue compressed by the weight of the patient. The oxygen-starved cells may eventually die causing ulcers. A patient susceptible to bed sores due to age or illness may suffer the onset or exacerbation of bed sores well within the time required for many surgical procedures.
Additionally, conventional surgical tables and inflatable mattresses also do not offer modularity. Instead, they are typically designed to provide a suite of functions without regard to a user's needs. For example, a plastic surgeon may wish to have an overlay mattress that offers only a Trendelenburg positioning function, while a postoperative acute care unit (“O.R. recovery room”) may need an overlay mattress that provides only thermal control. Unnecessary functions and their controls may cause confusion, create risks of inadvertent activation, complicate maintenance and increase cost. A modular product could be tailored (by the manufacturer, vendor or user) to include those components that provide desired functionality, while excluding unnecessary components. Such modularity can simplify use, reduce risks, facilitate maintenance and decrease cost.
Thus, an overlay mattress is needed to facilitate patient positioning, provide thermal comfort and alleviate the risk of bed sores. The overlay mattress should be radiolucent, modular and work with existing operating room tables and mattresses. Additionally, the overlay mattress should achieve the desired range of positioning quickly and easily.